Protecting socket for spark plugs



Get. i3, T1936. R. MTAILLER 2,057,390

PROTECTING SOCKET FOR SPARK PLUGS Filed 001;. 4, 1935 Patented Oct. 13, 1936 PATENT OFFICE PROTECTING SOCKET FOR SPARK PLUGS Ren Louis Mtailler, Courbevoie, France Application October 4, 1933, Serial No. 692,177 In France May 12, 1933 5 (Intime.4 (Cl. 12S-469) This invention relates to improvements in and relating to protecting sockets for spark plugs.

Protecting sockets for spark plugs are known which comprise a socket screwed into the head of the engine cylinder and the lower end of which terminates in a kind of bridge provided with or forming two lateral openings opposite to the points of the spark plug screwed into said socket. The bridge serves as a bafiie against which oil or other impurities which may be present in the cylinder are projected and broken up, so that the points of the spark plug are sufficiently protected.

In the present state of the art internal combustion engines are designed to operate at very high pressures and said engines usually have six and even eight cylinders.

On the other hand in certain types of engines of low and of medium power the combustion chamber is reduced in size and the free space between the lifted Valves and the inner face of the cylinder head is often not larger than 6 to 10 millimeters. As a result of Y lthis, protecting devices cannot be satisfactorily used in modern engines.

In fact, with the compression ratios used at the present time, even in a normal combustion chamber the protecting screen of the socket projecting into said chamber is overheated and brought to red heat, which causes self ignition.

Furthermore and particularly in engines of low and medium power it happens that operators mount the protecting socket Without taking into consideration whether the lifting of the valves or of the piston corresponds or not to the height of the bridge and of the screen of the protecting socket. As a result of this, the valves abut against the socket and become spoiled. As to the piston, it may be beaten in.

Moreover it may happen, in all events, that the screen of the protecting socket fuses, which may involve very serious consequences.

This invention has for its object to provide a novel protecting socket of the above mentioned kind through which the above mentioned drawbacks may be obviated.

The protecting socket according to the invention is constructed so that its protecting parts do not project into the combustion chamber and are in direct contactwith the mass being cooled by the water circulation in the head of the cylinder, so that they do not exceed the normal temperature of the engine.

In the appended drawing- Figure 1 is an elevational sectional view of l The present invention, as shown in Figures 2 a protecting socket of known type as mentioned above. Said socket is shown comparatively with regard to the protecting socket according to the invention.

Figure 2 is a perspective view of a form of socket according to the invention.

Figure 3 shows the same device mounted on the head of the engine cylinder.

Figures 4, 5, 6, '7 and 8 show several other modified forms of the socket according to the present invention.

FiFig. 9 is a sectional view taken on line 9-9 of t In Figure 1 the socket I receives, screwed into its thread 2, a spark plug (not shown). Said socket is screwed by means of its lower part 3, which is correspondingly threaded, into the cylinder head 4 of the engine. 5 is the bridge which is integral with the threaded part 3 and forms two lateral openings corresponding to the points of the spark plug and through which the ignition takes place. 6 is the screen or baille which protects said points in the above set forth manner.

As may be seen, when the socket is screwed into the head of the cylinder, if said socket is the socket I of Figure 1, the bridge 5 and the screen or baille 6 are in the interior of the combustion chamber 1. This involves the inconveniences which have already been mentioned,

and 3, comprises a hollow body or socket I having a base portion 3 of reduced diameter. Base portion 3 is externally threaded so that it can be screwed into an ordinary spark plug receiving port in the cylinder head 4 of an internal combustion engine. The bore in the upper portion of the socket I is internally threaded at 2 to receive a spark plug. As clearly shown in Figures 2 and 3, the lower portion of the base 3 carries a baille 6 in the form of a circular plate having segmental portions removed from opposite sides thereof to provide at side faces 6' and 6". With this construction, segmental passages I2 and I3, respeetively,eare provided between the flat sides 6' and i" and the wall of the port in the cylinder head 4.

Batlle 6 is secured to the base 3 by means of the bridge elements 5. These elements 5 maintain the upper surface of baille 6 spaced from 50 the lower edge of base 3 to provide wide lateral ports 8. Ports 8 provide communication between the interior 3 of the base 3 and the segmental passages I2 and I3.

As iS Obvious from Figures 2 and 3, the thread- 55 ed base can be made integral with a plate closing the bottom thereof and converted into the nished structure by cutting laterally into opposite sides of the base I above the plate to form ports 8 and bridges 5 and by cutting segments from each side of the plate to form the baille 6.

It will be noted from the showing in Figure 3 that the sum of the lengths of base 3 and the bridge and the thickness of bale 0 is equal to the thickness o1' the cylinder head wall so that the lower surface of baille 6 is flush with the inner surface of the cylinder head. This construction avoids the disadvantage of the prior art devices which project into the combustion space of the cylinder of an engine.

With the above-described construction, the combustible mixture will ilow through the segmental ports i2 and i3 between screen or baille 8 and the threaded opening in the cylinder wall in a direction parallel to the axis of the base I, then laterally through ports or openings 8, and ilnally through the interior bore oi! the base I in a direction axially thereof to the electrodes of the spark plug. Thus. the mixture flows in a zigzag path from the combustion chamber to the electrodes of the spark plug.

In the form shown in Figure 4 the openings l have been replaced by slots 8' which extend in a suitable direction.

In the form shown in Figure 5 said slots are replaced by holes 8".

In the form shown in Figure 6 the lateral openings 8 have been omitted as well as the slots 8' and the holes 8" and in the interior of the threaded part 3 a baille 9 is provided which coacts with a second baille replacing the screen 8.

'I'he protecting sockets shown in Figures 7 and 8 are formed of two parts:a main body i provided with inner threads 3 and outer threads l', and a threaded member l I adapted to be screwed into the inner threads 3 and comprising a bridge 5 integral with a screen 6.

In Figure '7 said member l I is screwed thrOugh the upper part of the socket, while it is screwed through its lower part in Figure 8.

In the device according to the invention the bailles of the protecting device and the inner chamber of frusto-conical shape produce at the moment of the explosion a burner eiIect which accelerates the propagation speed oi' the ignition in the gases and meliorates the eiiiciency of the engine.

Furthermore, the electrodes and insulating parts or materials are better protected inasmuch as there can be no lateral projection, since the inlet ports or openings for the gases are set in the threaded part oi' the cylinder head.

I claim as my invention:

1. A lsocket for spark plugs for high compression internal combustion engines having small combustion chambers, comprising a substantially cylindrical hollow body interiorly threaded to receive a spark plug, the exterior of said body being formed to receive a wrench and having its lower base portion exteriorly threaded for securing the body in a threaded opening in a cylinder wall, the length of the exteriorly threaded base portion of the socket being equal to the thickness of the cylinder wall, a solid thick plate closing the lower part of the threaded base of the socket and adapted to have its lower surface ush with the inner wall o1'. the combustion chamber of the cylinder, the lower portion of the threaded base oi the socket above said plate, and said plate being cut away on opposite sides of provide zigzag ducts for the passage of jets of gas from the combustion chamber into the interior of said socket.

2. A socket for spark plugs for high compression internal combustion engines having small combustion chambers, comprising a substantially cylindrical hollow body interiorly threaded to receive a spark plug, the exterior of said body being formed to receive a wrench and having its lower base portion exteriorly threaded for securing the body in a threaded opening in a cylinder wall, the length vof the exteriorly threaded base portion of the socket being equal to the thickness oi' the cylinder wall, a solid thick plate closing the lower part of the threaded base of the socket and adapted to have its lower surface ilush with the inner wall of. the combustion chamber of the cylinder, the lower portion ot the threaded base of the socket being cut away on opposite sides above said plate and the corresponding sides of said plate being cut away so that the plate has a width greater than the interior diameter of the base to provide a zigzag path for the iiow of jets oi' gas from the combustion chamber into the interior of said socket.

3. A protecting socket for spark plugs, comprising a hollow body adapted to receive the spark plug, said body having a base adapted to extend through the cylinder wall or an internal combustion engine, the base being of a length equal to the thickness of the cylinder wall, and a baille provided at the end of the base having wide ports on each side thereof providing communication between the combustion chamber of the cylinder and the interior oi' said body to cause the charge to iirst impinge the bame and then follow a zigzag path to the spark plug and thereby atomize the oily and carbonaceous particles.

4. A protecting socket for spark plugs, comprising a hollow body provided at its end adapted to enter a spark plug port of an engine cylinder with a baille having two flattened sides, the hollow body having two lateral ports directly above the flattened sides of the baille and cooperating with the baille to provide a zigzag path from the engine cylinder to the spark plug.

5. A protecting socket for spark plugs, comprising a. hollow body having a base adapted to enter a spark plug port of an engine cylinder, and a baille covering the end of the base of a diameter greater than the interior diameter of the base to avoid direct projection of non-atomized particles from the cylinder onto the spark plug.

REN LoUrs MrrAmnR. 

